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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator
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作者 Yang Zhang Sheng-Quan Yan +36 位作者 Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li xiao-fei wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期136-143,共8页
The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides... The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated. 展开更多
关键词 Accelerator mass spectrometry Wien filter Isobar separation SUPERNOVAE Chang'e-5 lunar samples
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Mitochondrial carrier homolog 2 increases malignant phenotype of human gastric epithelial cells and promotes proliferation,invasion,and migration of gastric cancer cells
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作者 Jing-Wen Zhang Ling-Yan Huang +3 位作者 Ya-Ning Li Ying Tian Jia Yu xiao-fei wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期991-1005,共15页
BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determi... BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determine the role of MTCH2 in gastric cancer.METHODS We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)cells.The mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial function.Mitochondrial function and ATP synthase protein levels were detected via Western blotting.RESULTS The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent tissues.Overexpression of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting apoptosis.CONCLUSION MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells. 展开更多
关键词 Gastric cancer Mitochondrial carrier homolog 2 ATP synthase ATP2A2 Mitochondrial permeability transformation pore
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Influence of a diet meal plan on pepsinogen I and II,gastrin-17,and nutritional status in gastric ulcer patients
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作者 Wei-Wei Zhang xiao-fei wang +1 位作者 Hai-Yan Yu Ling-Fang wang 《World Journal of Clinical Cases》 SCIE 2024年第21期4574-4581,共8页
BACKGROUND Gastric ulcers(GUs)have a high risk of clinical morbidity and recurrence,and further exploration is needed for the prevention,diagnosis,and treatment of the disease.AIM To investigated the effects of a diet... BACKGROUND Gastric ulcers(GUs)have a high risk of clinical morbidity and recurrence,and further exploration is needed for the prevention,diagnosis,and treatment of the disease.AIM To investigated the effects of a diet plan on pepsinogen(PG)I,PG II,gastrin-17(G-17)levels and nutritional status in patients with GUs.METHODS A total of 100 patients with GUs treated between May 2022 and May 2023 were enrolled,with 47 patients in the control group receiving routine nursing and 53 patients in the experimental group receiving dietary nursing intervention based on a diet plan.The study compared the two groups in terms of nursing efficacy,adverse events(vomiting,acid reflux,and celialgia),time to symptom improvement(burning sensation,acid reflux,and celialgia),gastric function(PG I,PG II,and G-17 levels),and nutritional status[prealbumin(PA)and albumin(ALB)levels].RESULTS The experimental group showed a markedly higher total effective rate of nursing,a significantly lower incidence of adverse events,and a shorter time to symptom improvement than the control group.Additionally,the experimental group’s post-intervention PG I,PG II,and G-17 levels were significantly lower than preintervention or control group levels,whereas PA and ALB levels were significantly higher.CONCLUSION The diet plan significantly reduced PG I,PG II,and G-17 levels in patients with GUs and significantly improved their nutritional status. 展开更多
关键词 Diet plan Dietary care Gastric ulcers Plan on pepsinogen I Plan on pepsinogen II GASTRIN-17
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Influence of highway space alignment continuous degradation in 3- dimensional space on autonomous vehicle trajectory deviation based on PreScan simulation
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作者 xiao-fei wang Nathanael Melkisedek Coulibaly Qiang Zeng 《Digital Transportation and Safety》 2023年第2期77-88,共12页
The advent of autonomous vehicles(AVs)is expected to transform the current transportation system into a safe and reliable one.The existing infrastructures,operational criteria,and design method were developed to meet ... The advent of autonomous vehicles(AVs)is expected to transform the current transportation system into a safe and reliable one.The existing infrastructures,operational criteria,and design method were developed to meet the requirements of human drivers.However,previous studies have shown that in the traditional horizontal and vertical combined design methods,where the two-dimensional alignment elements change,there are varying changes in curvature and torsion,which cause the continuous degradation of the spatial curve and torsion.This continuous degradation will inevitably cause changes in the trajectory of Autonomous Vehicles(AVs),thereby affecting driving safety.Therefore,studying the characteristics of autonomous vehicles trajectory deviation has theoretical significance for optimizing highway alignment safety design.Driving simulation tests were performed by using PreScan and Simulink to calibrate the lateral deviation.A machine learning approach called the Gradient Boosting Decision Tree(GBDT)algorithm was implemented to build a model and express the relationship between space alignment parameters and lane deviation.The results showed that the AV’s driving trajectory is significantly affected by the space alignment factors when the vehicle is driving in the inner lane,the downhill section,and the left-turn section.These findings will provide a novel perspective for road safety research based on autonomous vehicle driving trajectories. 展开更多
关键词 Autonomous Vehicles(AVs) Trajectory Deviation(TD) Traffic Safety Spatial Alignment Prescan CURVATURE TORSION
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The bZIP transcription factor MdHY5 regulates anthocyanin accumulation and nitrate assimilation in apple 被引量:39
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作者 Jian-Ping An Feng-Jia Qu +4 位作者 Ji-Fang Yao Xiao-Na wang Chun-Xiang You xiao-fei wang Yu-Jin Hao 《Horticulture Research》 SCIE 2017年第1期246-254,共9页
The basic leucine zipper(bZIP)transcription factor HY5 plays a multifaceted role in plant growth and development.Here the apple MdHY5 gene was cloned based on its homology with Arabidopsis HY5.Expression analysis demo... The basic leucine zipper(bZIP)transcription factor HY5 plays a multifaceted role in plant growth and development.Here the apple MdHY5 gene was cloned based on its homology with Arabidopsis HY5.Expression analysis demonstrated that MdHY5 transcription was induced by light and abscisic acid treatments.Electrophoretic mobility shift assays and transient expression assays subsequently showed that MdHY5 positively regulated both its own transcription and that of MdMYB10 by binding to E-box and G-box motifs,respectively.Furthermore,we obtained transgenic apple calli that overexpressed the MdHY5 gene,and apple calli coloration assays showed that MdHY5 promoted anthocyanin accumulation by regulating expression of the MdMYB10 gene and downstream anthocyanin biosynthesis genes.In addition,the transcript levels of a series of nitrate reductase genes and nitrate uptake genes in both wild-type and transgenic apple calli were detected.In association with increased nitrate reductase activities and nitrate contents,the results indicated that MdHY5 might be an important regulator in nutrient assimilation.Taken together,these results indicate that MdHY5 plays a vital role in anthocyanin accumulation and nitrate assimilation in apple. 展开更多
关键词 HY5 NITRATE ASSIMILATION
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Clinical and prognostic significance of raf kinase inhibitory protein expression in gastrointestinal stromal tumors 被引量:6
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作者 Yang wang Juan-Juan Chen +1 位作者 xiao-fei wang Qiang wang 《World Journal of Gastroenterology》 SCIE CAS 2018年第23期2508-2517,共10页
AIM To detect the expression of Raf kinase inhibitory protein(RKIP) in gastrointestinal stromal tumors(GISTs) and to analyze its relationship with clinicopatholgical characteristics and prognosis of this disease.METHO... AIM To detect the expression of Raf kinase inhibitory protein(RKIP) in gastrointestinal stromal tumors(GISTs) and to analyze its relationship with clinicopatholgical characteristics and prognosis of this disease.METHODS Sixty-three patients with pathologically diagnosed GISTs who underwent surgical resection at the Shengjing Hospital of China Medical University from January 2011 to January 2015 and had complete clinical,pathological,and follow-up data were included. Immunohistochemical method was used to detect the expression of RKIP in GIST tissue samples from these patients. KaplanMeier method was used to calculate the survival rate of 60 patients with complete follow-up data,and Cox regression analysis was performed to identify factors affecting the prognosis of patients GISTs to evaluate further the diagnostic and prognostic value of RKIP in GISTs.RESULTS In GIST tissues,RKIP positive signals,manifesting as brownish yellow or brown granules,were located in the cytoplasm or on the membrane. Of 63 tissue samplesincluded in this study,34(54%) were positive and 29(46%) were negative for RKIP expression. Statistical analysis showed that RKIP expression in GISTs was significantly associated with tumor size,National Institutes of Health(NIH) risk grade,and mucosal invasion,but had no significant association with age,gender,tumor location,or the number of mitotic figures. Univariate Kaplan-Meier analysis revealed that the 1-,3-,and 5-year survival rates were 94.4%,89.2%,and 80.5% for patients with positive RKIP expression,and 88.6%,68.2%,and 48.2% for patients with negative RKIP expression,suggesting that patients with high RKIP expression had significantly higher survival rates than those with low expression(Log-rank test,P = 0.0015). Cox regression analysis demonstrated that NIH risk grade was significantly associated with the prognosis of GISTs(P = 0.037),suggesting that NIH risk grade is a significant predictor of the prognosis of GISTs. RKIP expression had a tendency to predict the survival of GISTs(P = 0.122),suggesting that RKIP expression may have appreciated value to predict the prognosis of GISTs.CONCLUSION This study demonstrated that:(1) RKIP expression in GISTs is associated with tumor size,NIH risk grade,and mucosal invasion,and low or no expression of RKIP predicts a high malignancy potential;(2) high RKIP correlates positively with the survival of patients with GISTs; and(3) RKIP expression has appreciated value for predicting the survival of patients with GISTs,although it is not an independent prognostic factor in GISTs. 展开更多
关键词 GASTROINTESTINAL STROMAL tumors RAF kinase INHIBITORY protein Immunohistochemistry Survival analysis
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Simulation of an imaging system for internal contamination of lungs using MPA-MURA coded-aperture collimator 被引量:5
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作者 Ting Zhang Lei wang +4 位作者 Jing Ning Wei Lu xiao-fei wang Hai-Wei Zhang Xian-Guo Tuo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第2期58-69,共12页
The nuclides inhaled during nuclear accidents usually cause internal contamination of the lungs with low activity.Although a parallel-hole imaging system,which is widely used in medical gamma cameras,has a high resolu... The nuclides inhaled during nuclear accidents usually cause internal contamination of the lungs with low activity.Although a parallel-hole imaging system,which is widely used in medical gamma cameras,has a high resolution and good image quality,owing to its extremely low detection efficiency,it remains difficult to obtain images of inhaled lung contamination.In this study,the Monte Carlo method was used to study the internal lung contamination imaging using the MPA-MURA coded-aperture collimator.The imaging system consisted of an adult male lung model,with a mosaicked,pattern-centered,and anti-symmetric MURA coded-aperture collimator model and a CsI(Tl)detector model.The MLEM decoding algorithm was used to reconstruct the internal contamination image,and the complementary imaging method was used to reduce the number of artifacts.The full width at half maximum of the I-131 point source image reconstructed by the MPAMURA coded-aperture imaging reached 2.51 mm,and the signal-to-noise ratio of the simplified respiratory tract source(I-131)image reconstructed through MPA-MURA coded-aperture imaging was 3.98 dB.Although the spatial resolution of MPA-MURA coded-aperture imaging is not as good as that of parallel-hole imaging,the detection efficiency of PMA-MURA coded-aperture imaging is two orders of magnitude higher than that of parallel-hole collimator imaging.Considering the low activity level of internal lung contamination caused by nuclear accidents,PMA-MURA coded-aperture imaging has significant potential for the development of lung contamination imaging. 展开更多
关键词 Lung internal contamination MPA-MURA Monte Carlo MLEM Spatial resolution Detection efficiency
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BTB-BACK-TAZ domain protein MdBT2-mediated MdMYB73 ubiquitination negatively regulates malate accumulation and vacuolar acidification in apple 被引量:8
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作者 Quan-Yan Zhang Kai-Di Gu +6 位作者 Jia-Hui wang Jian-Qiang Yu xiao-fei wang Shuai Zhang Chun-Xiang You Da-Gang Hu Yu-Jin Hao 《Horticulture Research》 SCIE 2020年第1期827-838,共12页
As an important primary metabolite,malate plays a key role in regulating osmotic pressure,pH homeostasis,stress tolerance,and fruit quality of apple.The R2R3-MYB transcription factor(TF)MdMYB73 was identified as a pro... As an important primary metabolite,malate plays a key role in regulating osmotic pressure,pH homeostasis,stress tolerance,and fruit quality of apple.The R2R3-MYB transcription factor(TF)MdMYB73 was identified as a protein that plays a critical role in determining malate accumulation and vacuolar acidification by directly regulating the transcription of aluminum-activated malate transporter 9(MdALMT9),vacuolar ATPase subunit A(MdVHA-A),and vacuolar pyrophosphatase 1(MdVHP1)in apple.In addition,the bHLH TF MdCIbHLH1 interacts with MdMYB73 and enhances the transcriptional activity of MdMYB73.Our previous studies demonstrated that the BTB-BACK-TAZ domain protein MdBT2 can degrade MdCIbHLH1 to influence malate accumulation and vacuolar acidification.However,the potential upstream regulators of MdMYB73 are currently unknown.In this study,we found that MdBT2 directly interacts with and degrades MdMYB73 through the ubiquitin/26S proteasome pathway to regulate malate accumulation and vacuolar acidification.A series of functional assays with apple calli and fruit showed that MdBT2 controls malate accumulation and vacuolar acidification in an MdMYB73-dependent manner.Overall,our findings shed light on the mechanism by which the BTB-BACK-TAZ domain protein MdBT2 regulates malate accumulation and vacuolar acidification by targeting MdMYB73 and MdCIbHLH1 for ubiquitination in apple.This information may help guide traditional breeding programs and fruit tree molecular breeding,and lead to improvements in fruit quality and stress tolerance. 展开更多
关键词 MALATE ubiquitin homeostasis
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Testosterone level and mortality in elderly men wit systolic chronic heart failure 被引量:4
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作者 Hai-Yun Wu xiao-fei wang +1 位作者 Jun-Hua wang Jiang-Yuan Li 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第5期759-763,共5页
Previous studies on the prognostic significance of serum levels of androgens in patients with chronic heart failure (CHF) have yielded conflicting results. The aim of this study was to examine the relationship betwe... Previous studies on the prognostic significance of serum levels of androgens in patients with chronic heart failure (CHF) have yielded conflicting results. The aim of this study was to examine the relationship between serum concentration of testosterone and mortality in men with systolic CHF. A total of 175 elderly men (age ≥60 years) with CHF were recruited. Total testosterone (TI') and sex hormone-binding globulin (SHBG) were measured, and estimated free testosterone (eFT) was calculated. The median follow-up time was 3.46 years. Of these patients, 17 had a TT level below 8 nmol I^-1 (230 ng dI^-1), 27 had an eFT level below 0.225 nmol I^-1 (65 pg ml^-1) and 12 had both. Using the age-specific tenth percentiles of TT and eFT in healthy men in our laboratory as cutoff points, the prevalences of TT and eFT deficiency was 21.7% (38/175) and 27.4% (48/175), respectively. Both TT and eFT were inversely associated with left ventricular ejection fraction (LVEF) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) (all P〈0.01). Kaplan-Meier curves for patients in low, medium and high tertiles according to TT and eFT level showed significantly different cumulative survival rate (both P〈0.01 by log-rank test). However, after adjustment for clinical variables, there were no significant associations of either TT or eFT levels with survival time (0R=0.97, 95% CI: 0.84-1.12, P=0.28 and 0R=0.92, 95% CI: 0.82-1.06, P=0.14, respectively). Our study showed that levels of TT and eFT are commonly decreased in elderly patients with systolic CHF and related to disease severity, but they are not independent predictors for mortality. 展开更多
关键词 free testosterone heart failure PROGNOSIS total testosterone
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基于BP神经网络和蚁群算法的机械手轨迹控制算法研究(英文) 被引量:5
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作者 李晶 汪晓飞 段新娥 《机床与液压》 北大核心 2019年第24期146-152,共7页
为了提高机械手运行的平稳性,实现机械手控制的精准度,采用BP神经网络和蚁群算法相结合的方法实现机械手轨迹控制。首先,建立机械手运动轨迹模型,然后利用神经网络算法对机械手主要参数进行训练,接着,将输出预测的运动轨迹与机械手期望... 为了提高机械手运行的平稳性,实现机械手控制的精准度,采用BP神经网络和蚁群算法相结合的方法实现机械手轨迹控制。首先,建立机械手运动轨迹模型,然后利用神经网络算法对机械手主要参数进行训练,接着,将输出预测的运动轨迹与机械手期望运动轨迹对比,以便求解更趋近于期望的最优参数。最后,借助蚁群算法对神经网络模型参数进行优化。经过实验证明:相比于传统BP神经网络算法,所提算法训练得到的角位移与期望角位移的拟合程度更高,且在空间三维坐标系的位移误差更小。 展开更多
关键词 BP神经网络 蚁群算法 机械手运动轨迹 角位移 隐含层节点
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Androgen deficiency in elderly men with systolic chronic heart failure 被引量:3
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作者 xiao-fei wang Jun-Hua wang Jiang-Yuan Li 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2010年第3期138-142,共5页
Objective Several previous studies have shown androgens deficiency in men with CHF, and 2 studies on the prognostic significance of serum levels of androgens in CHF patients have yielded conflicting results. The aim o... Objective Several previous studies have shown androgens deficiency in men with CHF, and 2 studies on the prognostic significance of serum levels of androgens in CHF patients have yielded conflicting results. The aim of this study was to examine the relationship between serum concentration of testosterone and mortality in men with systolic CHE Methods A total of 175 elderly (age ≥ 60 years) men with CHF were recruited. Total testosterone fiT) and sex hormone binding globulin (SHBG) were measured, and free serum testosterone (eFT) was calculated. The median follow-up time was 1262 days. Results During follow-up 54 (30.9%) patients died. TT and eFF deficiency was found in 21.7% (38/175) and 27.4% (48/175) patients, respectively. Both TT and eFT were inversely associated with LVEF and NT-proBNP (all P〈0.01). Kaplan-Meier curves for patients in low, medium and high tertiles according to TF and eFT level showed significantly different cumulative survival rate (both P〈0.01 by log-rank test). However, after adjustment for clinical variables, there were no significant associations between either Tr or eFT levels or survival time (OR=0.97, 95% CI, 0.84-1.12, P--0.28; and OR=0.92, 95% CI, 0.82-1.06,/'=0.14, respectively). Conclusion Our study showed that although levels of TT and eFT are commonly decreased in elderly patients with systolic CHF and related to disease severity, they are not independent predictors for mortality 展开更多
关键词 Total testosterone free testosterone heart failure PROGNOSIS
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The apple 14-3-3 protein MdGRF11 interacts with the BTB protein MdBT2 to regulate nitrate deficiency-induced anthocyanin accumulation 被引量:4
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作者 Yi-Ran Ren Qiang Zhao +4 位作者 Yu-Ying Yang Tian-En Zhang xiao-fei wang Chun-Xiang You Yu-Jin Hao 《Horticulture Research》 SCIE 2021年第1期265-278,共14页
Nitrogen is an important factor that affects plant anthocyanin accumulation.In apple,the nitrate-responsive BTB/TAZ protein MdBT2 negatively regulates anthocyanin biosynthesis.In this study,we found that MdBT2 undergo... Nitrogen is an important factor that affects plant anthocyanin accumulation.In apple,the nitrate-responsive BTB/TAZ protein MdBT2 negatively regulates anthocyanin biosynthesis.In this study,we found that MdBT2 undergoes posttranslational modifications in response to nitrate deficiency.Yeast two-hybrid,protein pull-down,and bimolecular fluorescence complementation(BiFC)assays showed that MdBT2 interacts with MdGRF11,a 14-3-3 protein;14-3-3 proteins compose a family of highly conserved phosphopeptide-binding proteins involved in multiple physiological and biological processes.The interaction of MdGRF11 negatively regulated the stability of the MdBT2 protein via a 26S proteasome-dependent pathway,which increased the abundance of MdMYB1 proteins to activate the expression of anthocyanin biosynthesis-related genes.Taken together,the results demonstrate the critical role of 14-3-3 proteins in the regulation of nitrate deficiency-induced anthocyanin accumulation.Our results provide a novel avenue to elucidate the mechanism underlying the induction of anthocyanin biosynthesis in response to nitrate deficiency. 展开更多
关键词 NITRATE GRF BTB
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Anterior bone loss after cervical disc replacement: A systematic review 被引量:3
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作者 xiao-fei wang Yang Meng +2 位作者 Hao Liu Ying Hong Bei-Yu wang 《World Journal of Clinical Cases》 SCIE 2020年第21期5284-5295,共12页
BACKGROUND Anterior bone loss(ABL)is a relatively easily neglected condition after cervical disc replacement(CDR).Whether this phenomenon is a radiological anomaly or a complication remains controversial.Several studi... BACKGROUND Anterior bone loss(ABL)is a relatively easily neglected condition after cervical disc replacement(CDR).Whether this phenomenon is a radiological anomaly or a complication remains controversial.Several studies have reported the clinical characteristics of ABL and speculated on the pathogenic mechanism based on a certain type of artificial disc,while the overall understanding of ABL is lacking.AIM To describe the prevalence,impacts,and risk factors of ABL after CDR.METHODS We searched the PubMed,Cochrane Library,and Excerpta Medica databases using the terms“bone loss”or“bone remodeling”or“bone absorption”or“osteolysis”or“implant loosening”or“implant migration”or“hypersensitivity”or“hyperreactivity”,“cervical disc replacement”or“cervical disc arthroplasty”or“total disc replacement”.Eligible manuscripts on the prevalence and impacts of ABL were reviewed by the authors.Data extraction was performed using an established extraction form.The results of the included studies were described narratively.RESULTS Six studies met the inclusion and exclusion criteria.One was a prospective study and the others were retrospective studies.A total of 440 patients with 536 segments were included.The artificial cervical discs included Bryan,Baguera-C,Discocerv,and Mobi-C.The prevalence of ABL ranged from 3.13%to 91.89%,with a combined overall prevalence of 41.84%.ABL occurred within 6 mo and stopped 12 mo after surgery.Several cases were noted to have a self-healing process.Severe ABL resulted in segmental kyphosis,implant subsidence,and persistent neck pain.ABL may be related to heterotopic ossification.Multilevel surgery may be one of the risk factors for ABL.CONCLUSION ABL is a common condition after CDR.The underlying mechanisms of ABL may include stress concentration and injury to nutrient vessels.ABL should be considered a complication after CDR as it was associated with neck pain,implant subsidence,and heterotopic ossification. 展开更多
关键词 Bone loss Bone remodeling Stress shielding Risk factor Systematic review
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Transition intensity calculation of Yb:YAG 被引量:1
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作者 Hong-Bo Zhang Qing-Li Zhang +4 位作者 Xing wang Gui-Hua Sun xiao-fei wang De-Ming Zhang Dun-Lu Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期448-453,共6页
The Yb:YAG is an excellent high-average power and ultra-short pulse laser crystal. Transition intensity parameters A(tp)~k and Huang–Rhys factors are fitted to its emission spectrum by the full-profile fitting met... The Yb:YAG is an excellent high-average power and ultra-short pulse laser crystal. Transition intensity parameters A(tp)~k and Huang–Rhys factors are fitted to its emission spectrum by the full-profile fitting method. Calculated results indicate that the emission spectrum of Yb:YAG at cryogenic temperature consists of three pure electron state transitions and two phononassisted transitions, one vibronic transition releases one-phonon of 3 cm^(-1), and the other vibronic transition absorbs onephonon of 22 cm^(-1). At 300 K, the phonon assisted transition of 3 cm^(-1) turns into two-or more-phonon assisted transitions.The procedure absorbing phonon can reduce the thermal load of Yb:YAG and improve the laser efficiency, which may be one of the reasons why Yb:YAG has excellent performance. The emission bands of Yb:YAG are broadened thermally, and the peak values decrease by several times. The emission cross sections of Yb:YAG determined by Fuchtbauer–Ladenburg(F–L) formula are remarkably different from those calculated with A(tp)~k, which indicates that it is necessary for a laser material to determine its transition intensity parameters A(tp)~kin order to reasonably evaluate the laser performance. 展开更多
关键词 transition intensity parameters rare earth PHOTOLUMINESCENCE Yb^3+ :YAG
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Low specific on-resistance GaN-based vertical heterostructure field effect transistors with nonuniform doping superjunctions 被引量:1
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作者 Wei Mao Hai-Yong wang +7 位作者 Peng-Hao Shi xiao-fei wang Ming Du Xue-Feng Zheng Chong wang Xiao-Hua Ma Jin-Cheng Zhang Yue Hao 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期426-431,共6页
A novel Ga N-based vertical heterostructure field effect transistor(HFET) with nonuniform doping superjunctions(non-SJ HFET) is proposed and studied by Silvaco-ATLAS,for minimizing the specific on-resistance(RonA... A novel Ga N-based vertical heterostructure field effect transistor(HFET) with nonuniform doping superjunctions(non-SJ HFET) is proposed and studied by Silvaco-ATLAS,for minimizing the specific on-resistance(RonA) at no expense of breakdown voltage(BV).The feature of non-SJ HFET lies in the nonuniform doping concentration from top to bottom in the n-and p-pillars,which is different from that of the conventional Ga N-based vertical HFET with uniform doping superjunctions(un-SJ HFET).A physically intrinsic mechanism for the nonuniform doping superjunction(non-SJ) to further reduce RonA at no expense of BV is investigated and revealed in detail.The design,related to the structure parameters of non-SJ,is optimized to minimize the RonA on the basis of the same BV as that of un-SJ HFET.Optimized simulation results show that the reduction in RonA depends on the doping concentrations and thickness values of the light and heavy doping parts in non-SJ.The maximum reduction of more than 51% in RonA could be achieved with a BV of 1890 V.These results could demonstrate the superiority of non-SJ HFET in minimizing RonA and provide a useful reference for further developing the Ga N-based vertical HFETs. 展开更多
关键词 GaN-based vertical HFETs nonuniform doping superjunctions minimized specific on-resistance breakdown voltage
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Surgical strategy used in multilevel cervical disc replacement and cervical hybrid surgery:Four case reports 被引量:1
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作者 xiao-fei wang Yang Meng +2 位作者 Hao Liu Ying Hong Bei-Yu wang 《World Journal of Clinical Cases》 SCIE 2020年第17期3890-3902,共13页
BACKGROUND Multilevel artificial cervical disc replacement and anterior hybrid surgery have been introduced as reliable treatments for multilevel cervical degenerative disc disease.Surgical techniques are important fo... BACKGROUND Multilevel artificial cervical disc replacement and anterior hybrid surgery have been introduced as reliable treatments for multilevel cervical degenerative disc disease.Surgical techniques are important for resolving patients’symptoms and maintaining the normal functioning of cervical implants.However,the use of inappropriate surgical strategies could lead to complications such as implant migration and neurological deficit.In this paper,we summarize our surgical strategies used in multilevel cervical disc replacement and hybrid surgery into five major notes.CASE SUMMARY We share the key notes and our surgical procedures in the form of four typical case presentations.All patients were diagnosed with cervical degenerative disc disease with myelopathy or radiculopathy and needed multilevel cervical spine surgery.The first case demonstrated that index levels indicating the presence of highly serious spinal cord compression required a prioritized decompression.The second case demonstrated that the disc replacement should be performed before fusion in cervical hybrid surgery.The third and forth cases demonstrated that a top-down implantation sequence was needed in continuous two-level cervical disc replacement.The symptoms of all patients were significantly relieved after surgery.CONCLUSION We hope that our surgical strategies can help improve the performance and outcomes of multilevel cervical spine surgery. 展开更多
关键词 Cervical disc replacement Cervical hybrid surgery Multilevel cervical spine surgery Surgical strategy Implant migration Case report
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The MdABI5 transcription factor interacts with the MdNRT1.5/MdNPF7.3 promoter to fine-tune nitrate transport from roots to shoots in apple 被引量:1
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作者 Ya-Jing Liu Ning Gao +6 位作者 Qi-Jun Ma Jiu-Cheng Zhang Xun wang Jing Lu Yu-Jin Hao xiao-fei wang Chun-Xiang You 《Horticulture Research》 SCIE 2021年第1期3131-3143,共13页
Nitrate is a major nitrogen resource for plant growth and development and acts as both a crucial nutrient and a signaling molecule for plants;hence,understanding nitrate signaling is important for crop production.Absc... Nitrate is a major nitrogen resource for plant growth and development and acts as both a crucial nutrient and a signaling molecule for plants;hence,understanding nitrate signaling is important for crop production.Abscisic acid(ABA)has been demonstrated to be involved in nitrate signaling,but the underlying mechanism is largely unknown in apple.In this study,we found that exogenous ABA inhibited the transport of nitrate from roots to shoots in apple,and the transcription of the nitrate transporter MdNRT1.5/MdNPF7.3 was noticeably reduced at the transcriptional level by ABA,which inhibited the transport of nitrate from roots to shoots.Then,it was found that the ABA-responsive transcription factor MdABI5 bound directly to the ABRE recognition site of the MdNRT1.5 promoter and suppressed its expression.Overexpression of MdABI5 inhibited ABA-mediated transport of nitrate from roots to shoots.Overall,these results demonstrate that MdABI5 regulates the transport of nitrate from roots to shoots partially by mediating the expression of MdNRT1.5,illuminating the molecular mechanism by which ABA regulates nitrate transport in apple. 展开更多
关键词 ABI5 nitrate ROOTS
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An Atomic Magnetometer with Spin-Projection Noise Proportional to (T_2)^(1/2)
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作者 Hai-Feng Dong xiao-fei wang +2 位作者 Ji-Min Li Jing-Ling Chen Yuan Ren 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第2期4-7,共4页
There is a comm on sense view for atomic magnetometers that their spin-projection-noises(SPNs) are inversely proportional to (T_2)^(1/2), where (T_2)^(1/2) is the transverse relaxation time. We analyze the current ato... There is a comm on sense view for atomic magnetometers that their spin-projection-noises(SPNs) are inversely proportional to (T_2)^(1/2), where (T_2)^(1/2) is the transverse relaxation time. We analyze the current atomic magnetometer types and give a counter-example of this common sense, which is the all-optical spin precession modulated threeaxis atomic magnetometer proposed by our group in 2015. Unlike the other atomic magnetometers, the SPN of this kind of atomic magnetometers is proportional to (T_2)^(1/2) due to the fact that the scale factor between P_x and B can be unrelated to the transverse relaxation time T_2. We demonstrate this irrelevance experimentally and analyze the SPN theoretically. Using short-pulse ultra-high power laser to fully polarize the atoms, the phenomenon that SPN decreases with T_2 may also be demonstrated experimentally and a new tool for researching SPN in atomic magnetometers may be realized. 展开更多
关键词 AN ATOMIC MAGNETOMETER with Spin-Projection Noise Proportional to T2
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Reduction of Dimerization Tendency Due to the Decrease in Hybridization Index by Inclusion of 4s and 4p Semicore States as Valence States in Mo_(n)(n=2-18)Clusters:A First-Principles Study
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作者 Zhao-ye Gong Zhi-qiang Sun +5 位作者 Yan-wen Ding Shuai Zhang Zhen-long Lv xiao-fei wang Li-ben Li Hai-sheng Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第5期639-648,I0004,共11页
Owing to the unique structural,electronic,and physico-chemical properties,molybdenum clusters are expected to play an important role in future nanotechnologies.However,their ground states are still under debate.In thi... Owing to the unique structural,electronic,and physico-chemical properties,molybdenum clusters are expected to play an important role in future nanotechnologies.However,their ground states are still under debate.In this study,the crystal structure analysis by particle swarm optimization(CALYPSO)approach is used for the global minimum search,which is followed by first-principles calculations,to detect an obvious dimerization tendency in Mo_(n)(n=2-18)clusters when the 4s and 4p semicore states are not regarded as the valence states.Further,the clusters with even number of atoms are usually magic clusters with high stability.However,after including the4 s and 4 p electrons as valence electrons,the dimerization tendency exhibits a drastic reduction because the average hybridization indices H_(sp),H_(sd),and H_(pd) are reduced significantly.Overall,this work reports new ground states of Mo_(n)(n=11,14,15)clusters and proves that semicore states are essential for Mo_(n) clusters. 展开更多
关键词 Density functional theory First-principles calculations Mo clusters Hybridization indices 4s and 4p Semicore states
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Elimination of Anti-spiral Waves by Local Inhomogeneity in Oscillatory Systems
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作者 Fu-cheng Liu xiao-fei wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第6期575-580,共6页
Anti-spiral waves are controlled in an oscillatory system by using a local inhomogeneity. The inhomogeneity acts as a wave source, and gives rise to the propagating plane waves, tt is found that there is a critical pa... Anti-spiral waves are controlled in an oscillatory system by using a local inhomogeneity. The inhomogeneity acts as a wave source, and gives rise to the propagating plane waves, tt is found that there is a critical pacemaking domain size below which no wave will be created at all. Two types of ordered waves (target waves and traveling waves) are created depending on the geometry of the local inhomogeneity. The competition between the anti-spiral waves and the ordered waves is discussed. Two different competition mechanisms were observed, which are related to the ordered waves obtained from different local inhomogeneities. It is found that traveling waves with either lower frequency or higher frequency can both eliminate the anti-spiral waves, while only the target waves with lower absolute value of frequency can eliminate the anti-spiral waves. This method also applies to outwardly rotating spiral waves. The control mechanism is intuitively explained and the control method is easily operative. 展开更多
关键词 Anti-spiral wave Traveling wave INHOMOGENEITY Oscillatory system
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